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What's the Difference Between Sudo & Su?

"The su command switches to the super user – or root user
– when you execute it with no additional options. You'll have
to enter the root account's password. This isn't all the su command
does, though – you can use it to switch to any user account.
If you execute the su bob command, you'll be prompted to enter
Bob's password and the shell will switch to Bob's user
account...

Sudo runs a single command with root privileges. When you
execute sudo command, the system prompts you for your current user
account's password before running command as the root user.